Method of staking blades



y 1960 K. R. STADTHAUS EI'AL 2,944,326

METHOD OF STAKING BLADES Filed June 2, 1955 20 Z/ WW United States Patent METHOD OF STAKING BLADES Kurt R. Stadthaus, Madeira, and Melvin Bobo, Reading,

Ohio, and Robert H. Schaefer, Stratford, Conn, a..- signors to General Electric Company, a corporation of New York Filed June 2, 1955, Sophie. 512,702

3 Claims. (Cl. 29--'156.8)

This invention relates to a method and means for staking blades and, more particularly, to a method and means for attaching blades such as rotor and stator blades as might be found in compressors and/or turbines. While compressors and turbines are used as an illustration, it is to be understood that the present invention is applicable to any device of a similar nature wherein blades must be attached to a rotating or a stationary member.

One of the common ways of attaching blades is by the conventional dovetail arrangement. Many modifications of this have been disclosed in the prior art to solve various problems. The machining required in such a fastening means is considerable, and consequentlythe cost of the in dividual blades is high. The method disclosed herein avoids most of the machining normally required and 7 A further object is to provide a. method and means of attaching blades by staking, using as few parts as possible and still maintaining a secure fastening arrangement that is easily reproduced from blade to blade.

Briefly described, .the invention consists in upsetting a blade base by coining to give adesired configuration thereto. The memberto which'the blade is attached is formedto exactly match the blade configuration and operation is also done by coining. -When the parts are assembled, the blade is held in position by staking it to the base member. The staking consists merely in deforming the base member to cause it to flow and thereby secure the blade in position by reason of the configuration given to the blade base. While the present invention will be illustrated with reference to a staked stator blade, it is applicable to many uses wherein a blade is to be fastened to a base member, and such uses may be apparent to those skilled in the art. Therefore, the staked stator blade application is merely intended to be illustrative of a specific application of the invention.

operation.

My invention will be better understood from the following description taken in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

In the drawings: 7

Figure 1 is a cross-sectional view of the coining operation performed on the blade base;

Figure 2 is a perspective view of the blade baseas formed by the coining operation; 7

Figure 3 is a partial plan View of a pierced ring in which the blade of Figure 2 is to be mounted;

'ice

Figure 4 is a cross-sectional view of the ringshowing the coining operation performed thereon;

Figure 5 is a partial cross-sectional view of the blade in position in the ring before staking;

Figure 6 is a view similar to Figure 5 showing the staking operation to join the parts together and;

Figure 7 is a partial perspective view of the staked blades.

Referring first to Figure 1, there is shown a blade 10 having a generally rectangular-sided shank or baseli (shown in dotted lines) integrally formed therewith. It is not important that the base :11 be of any particular configuration at this stage nor of any particular finish. It is merely necessary that enough material be in the base to fulfill the requirements of the subsequent coining operation. The blade is placed in a coining die which has the con-figuration which is to be formed on the blade base. As shown, die 12 has an aperture 13 therein in which the blade base is placed. The sides of the aper-' 'ture 13 are preferably tapered as at 14 to a desired con-' figuration. The remaining necked-down portion 15 of the die 12 holds the blade in position within .the die. It will be' understood that the taper of sides14jmay be made to any desired dimensiondepending on theparticular 'blade jinvolved. A pair of opposite inwardly' directed. members or bosses 16 are 'providedon the tapered sides. 14. Bosses 16 are preferably symmetrically located with, respect to each other although it is not necessary that they be so located and more than one may be providcdvandj different shapes may housed, and the term groove as produced by bosses 1'6 intended to include all equivalents inasmuch as it is only necessary to create an irregularity,

that the subsequent deforming operation may anchor on as will be apparent hereinafter. Bosses 16 extend lengthwise of the blade base and are preferably terminated short of the edge of the blade base.

When the blade, as located in die 12, is struck. by

punch 17 moving in the direction shown by the arrow,

the base 11 is angularly deformed to conform to the shape of the die aperture, the metal in the blade base flowing outwardly to fill the aperture. This operation is termed a coining operation to provide a given configuration' to the blade base and may be a punch press or roll coining result of the coining operation, has tapered sides 18 with staking grooves i9therein extending across the bladebase and preferably terminating short of the'edges of the blade of bosses 16 on the blade base as a result of fthe coining operation by punch 17. The formation of the blade base in the aforementioned manner provides for exact duplication from blade to blade so that all the blades so formed are exactly the same. ing the blade base is much cheaper and faster than machining each blade individually.

The blade, as it will be used, having been formed, it is now necessary to prepare the member in which the blade is to be mounted. Referring now to Figure 3, there is shown a ring member 24 before forming the curve therein such as might be used when the blades are to form the stator as in a compressor. Ring member 20 has pierced therein, either before or-after curving, a series of slots 21 that are directed at a suitable angle across the ring as shown. Referring next to Figure 4, there is shown a cross-sectional view of the ring member of Figure 3. Slots 21, as a result of the piercing operation, may be broached if required to provide smooth sides to the slots Patented July 12, 1960* As seen in Figure 2,, the blade base, as a In addition, this method. offormmoving in the. direction shown by the arrow, against a stop member 23. By the use of this coining operation, a slot 24, having continuous tapered sides, is produced to exactly match the taperedv sides 18 of the blade base. This coining. operation. may beperformed over and over again to produce formed slots 24. that are exact duplicates oi one another.

The blade base 11 and ring member 20 having been prepared, the next step in; the method is to attach the two members together by staking, As shown in Figure 5, the blade is droppedinto the ring, member, the tapered sides of the blade base conforming exactly to the tapered sides oi slot 24 in the ring, member. As shown in Figure 6,

a stop member, such as 25, is brought against the ring.

20 on one side, and as herein shown it may be brought. against the blade side of the ring. A staking die 26 is forced against the ring. Staking die 26 has pressure applying extensions 17 thereon to straddle the base of the blade. By the application of. pressure to, staking die 26, the; metal of ring. 20 is caused to flow into the staking grooves 19 in the blade base onv both sides thereof. Thus, the blade is securely locked. to the curved ring member 20, to provide av staked bladeassembly as shown in Figure 7.

The finished assembly may be brazed in addition to the staking. by the application of a high temperature braze to the joint between the blade base and the ring. The hraze is. drawn in by capillary action to provide a cementing. bond between the blade base and the ring in. addition. to the securement. obtained by the staking.

The; tapered sides. herein shown are ameans of locking. the. blade in position in the ring from movement in one direction. The, upsetting of the ring 2%} into staking grooves. 19 is an additional locking; means for the blade to. prevent movement in both directions. If brazing is additionally used on the staked blades, the fastening will be even more secure. As shown in Figure 6, it will be obvious that the staking may be done onthe opposite side ofthe ringirom that shown. In such a case, the staking die 26 may require provision for the blade so the operation. shownain Figure 6 is the preferable way of staking.

Whilewehave hereinbefore-showrr an improved method of staking blades. to provide easily reproduced members in lightweight construction, it will be apparent to those skilled the art that the method andv means of. attachmentmay have other uses that fall within the scope of the appended claims...

We claim:

1. The methodof staking. bases of compressor or turbine blades to: a; base member comprising, coining, the blade base in a die. to provide tapered sides thereon and simultaneously coining. grooves" into said: sides to extend only part: ofthe length-.01.- said sides, piercing, a slot inthe base member, coining the base member to form tapered sides in the slot which exactly match the taper of said blade base sides, assembling said blade base in said slot, and deforming the base member to cause the material of the base member to flow into said grooves to secure the blade base and member together.

2. The method of staining bases of compressor or turbine blades to a ring member comprising, coining the blade base ina die to provide tapered sides thereon and simultaneously coining parallel grooves. into said sides to extend only part or the lengthof said sides, piercing a slot in the ring. member, coining the met-abet to form tapered sides in the slot which exactly match the taper of said blade base sides, assembling the blade base in said slot, and deforming the base member with a die straddling the blade base to cause the. material of the base member to flow into said grooves to secure the base and member together.

3. The method of staking bases of compressor or turbine blades to a ring member comprising, coining. a rough blade base to provide a taper on the sides. thereof extend ing toward the blade, simultaneously coining: a groove in each of said tapered sides to provide parallel grooves ex tending less thanthe extent of the. sides, piercing the ring member to form a slot therein, smoothing the sides of said slot, coining the ring material witha smooth tapered die to form tapered sides in the slot which, exactly match the taper of the blade base sides, fitting. the tapered parts together, staking the ringmember, simultaneously oneach side of the blade base parallel with said grooves to cause the material of said ring ,member to flow into said. grooves and grip the, blade base sides, and flowing brazing. material into the joints between the blade base and ring. member.

References Gited in the" file of this patent UNITED STATES PATENTS 868,4;1'9 Oct. 15, 1907" 905,460 Rice Dec. 1 1 908 933,379 Ljungstrom Sept; 7, L909 953,563 Thiel! M arL 29; 1910 958,239-' Emden et al'.- May 17,- 1910 1,101,645 Ljungstrom: June 30} 191% 1,141,190 Kilker J une' 1*, 191$" 1,470,506 Steenstrup Oct; 9; 1923 1,773,410 Selah -Aug.- 19} 1930 2,278,040 Allen Mar: 3&1, 1942 2,279,258 Ailleni s Apr. 7, 1942 2,673,709 Barnes Mar. 30; 1 1 2,680,286 Will'goos June 8 19 54 FOREIGN PKTENTS' 552,290 France Jam 19,.- L923? 334-,0l9 Italy Jam- 20 1966 

